Keyboard



Patented Feb. 2g, l1,936

PATENT OFFICE KEYBOARD Alexander Adolf Carlo Degen, Harrow,

England,

assigner to Bell Punch Company Limited, London, England Application September 10, 1934, Serial No. 743,477 In Great Britain June 11, 1934 9 Claims.

This invention concerns improvements in and relating to key operated ticket issuing and ticket printing and issuing machines and has for its Aobject to provide an improved key board for the machine which gives satisfactory key operation whilst protecting the keys against damage and, in one form of construction, rendering the key board dust and water proof.

'I'he invention comprises a key operated ticket issuing or ticket printing and issuing machine, provided with a key board that is flush and devoid of all projections.

Further, the invention consists in the provision, in a key operated ticket issuing or ticket printing and issuing machine of a key board comprising a cover plate positioned over and adjacent to the ends of. the key levers or stems of the keys to be manipulated in such a manner that the said ends do not extend substantially above the said plate and are operable manually through openings (one for each key) in the plate.

The invention also consists in the provision in a key operated ticket issuing or ticket printing and issuing machine, of an elastic or flexible membrane mounted 4immediately under one or more openings in a key board cover plate and over the ends of the key levers or stems to be manipulated, in such a manner as to be exed in operating any of the keys through the opening by pressure applied to the said key through the membrane.

In order that the invention may be fully understood, reference is directed to the accompanying diagrammatic drawing, in which:-

Figure 1 is a sectional side elevation of a machine provided with a key board constructed in accordance with the invention;

Figure 2 is a plan of a portion of the key board shown in Figure 1;

Figures 3 and 4 are views similar to a portion of Figure 1 but illustrating two modifications of the invention; and

Figure 5 is a sectional view similar to Figure 3 but showing a modified construction according to which instead of providing an opening in the cover plate over each key, a single opening common to several keys and extending thereover collectively is provided.

Referring to the Figures l and 2, the machine comprises a casing l having a front wall 2 and an intermediate wall 3 through slots 4 in which key levers 5 extend from a pivot 6. The upturned ends o1. the key levers are bent over as shown at 'I and lie just below a rubber membrane 8 disposed parallel to the key board and mounted over the ysaid upper ends 'l by being clamped below a top cover plate Sand ledges I on the walls 2 and 3. An opening in the form of a nger hole I l is provided in the plate 9 over each of the respective keys so that a key may be depressed by inserting av finger through one of the said holes and flexing the membrane 8 lying immediately below the finger hole, downwardly by pressure applied to the said key through the membrane. The tops of the keys can be domed as shown to 10 cause the membrane normally to be pressed as a shallow convex projection into the corresponding nger hole.

The membrane may be provided with key designations such as numbers as shown in Figure 2 15 which appear through the key holes alternatively the designations can be provided upon the plate adjacent to the nger holes.

Bars may be provided between adjacent keys immediately below the membrane 8 if necessary 20 with keys of. light operation to prevent the depression of the membrane in operating one key from inadvertently operating a key adjacent thereto.

The plate 9 can lie flush with the top of the 25 machine or can be stepped in relation thereto.

In the arrangement shown in Figure 3 the membrane 8 is provided with button like projections l2 which are formed integrally with the membrane and which extend through the finger holes so as to lie flush with the top of the plate 9. The key designations can be in either of the forms described with reference to Figures 1 and 2.

In the arrangement shown in Figure 4, the buttons l2 are displaceably mounted in the nger 35 holes and can either be cemented with the membrane 8 or confined by an annular edge I3 of the button between the said membrane and the plate 9. The buttons are substantially flush with the top of the plate 9 and bear the key designations, 40 or such designations can be provided upon the plate 9 adjacent to the finger holes.

The turned over portion l of the key lever can be dispensed with if desired particularly in the arrangements shown in Figures 3 and 4 in which 45 the buttons serve to distribute the stresses applied to the membrane during the operation of the keys.

Referring to Figure 5, the single opening hereinbefore referred to which is common to several keys, extending over them collectively, is marked I4, the edges of the opening at the ends thereof only being shown in the figure. As shown the opening extends over 3 keys which are marked l as in the previous figures and the rubber memappreciated that projecting key levers, stems or buttons are avoided and the provision of the,

membrane sho-wn in the various ligures makes the key board dust and water prooi?.Examplesqp -5 key operated ticket issuing machinestp which the invention can be applied are disclosed in United Kingdom patent specivcations No. 1?"15513:VVAV

and No. 282,581.

What I claim and desire to secure by Letters Patent of the United States is:-`

l. `In a key operated ticket... issuing or v ticket printing and issuing machine, a keyboardcomj- ,b prising a plurality of operable keys,l a.'coverfr'alate'y4 positioned over and adj acentl to the'manipulative.l ends of said keys, said platehaving at, leastvone, opening through which said/keys4 can be operated, and a exible membrane vso mountedas to extend between said plate and said keys and permit'rnanl l, ual operation of vsaid keys through said opening,

by fl'exure of said membrane.

2. In a key operated ticket issuing or ticket t: printing and issuing machine, a key board ,com-f ,l

prising a plurality of 'operable keys, a coverplate positionedover and adjacent, to the manipular mounted asv to extend betweenQsaid'plate4 andsaid keys, and openings in said plate, Vone to eachkey'` and positioned thereover so that eac/h .vkey can be operated through the respectivespening :flexure of said membrane.

3. In a key operatedticket issuing or ticket,V printing and issuing machine clairedin claim 2, suchua disposition of the manipulative ,ends ofl said keys that the iiexible membrane is normally'r flexed by said ends in an upwardly domed configuration in each of the openings in the cover plate.

4. In a key operated ticket issuing or ticket printing and issuing machinev as claimed in claim 2, the provision of button like projections on the iiexible membrane, one extending upwardly into each of the openings in the cover plate.

5. In a key. operated ticket issuing or ticket printing and issuing machine as claimed in claim 2, theprovision of finger buttons slidably mounted onein each of the openings of the cover plate above the membrane.

6. In a key `operated ticket issuing or ticket printing and issuing machine as claimed in claim 2, the provision Aof ilanged finger buttons slidably mounted one in each of the openings of the cover plate above the membrane and with the flange of the button exten-ding between the membrane and the cover plate around the opening.

'7. In a key operated ticket issuing machine, a

keyboard comprising aV plurality of operablevkeys, Ya cove-r plate having at least one opening at the topsV of said keys, and a ilexible membrane clos-Y ing said openingand overlying the tops of saidA keys, whereby the keys may be manually de- A, pressed by ilexure of said membrane..

8. In a key-operated ticket issuing machine, in-

cluding at least one key, a cover plate having an opening at the top of the key, and a flexible mem-f brane extending across the said opening `so as to close it and overlie the topi of the key, vwhereby. the key may be manually. depressed by exure of Y 4 i said membrane.

tive'ends of saidv keys, a flexible membrane, so

9. In a key-operated ticket issuing machine, a keyboard comprising a plurality of operable keys,

a cover plate formed to provide access to said keys to permit manualoperation of said keys, and a exible membrane overlying the tops of said keys and underlying said cover plate whereby the keys 4c may be manually depressed by iiexure Vof said membrane.

ALEXANDER ADOLF CARLO; DEQEN, 

